Rock-drill chuck.



No. 856,877. PATENTED JUNE ll, 1907. C. A. HU UIST.

ROCK DR CHUCK. APPLICATION FILED SBF120, 190e.

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WITNESSES: INVENTOR @.246 Vif (firming) NTITED STATES PATENT OFFICE..

ROCK-DRILL CHUCK.

Specification of Letters Patent.

Patented June l1, 1907.

Application iiled September 20,1906. Serial No. 335.405.

T0 all whom it may con/cern:

Be it known that l, Onnutns A. Ilm/r- QUrs'r, a citizen of the United States, residing at Lowell, in the county' ot' Cochise and Territory et Arizona, have invented new and useful improvements in Rock-Drill Chucks, ot which the following is a speci'lication.

My invention relates to an improved rock drill holding chuck, and it consists in the combination and arrangement of parts, and in details of construction which will be more fully explained by reference to the accompanying drawings, in which Figure l is a side elevation. F 2 is a transverse section. F l is a longitudinal section of the key and bushing, showing the drill-shank in elevation.

In rock drills it is customary to secure the drill shank to the piston rod or other part by which the drill is actuated, by means ot a chuck having an opening to receive the end of the drill shank, and by means of a key and bolts the drill is clamped into the chuck.

It is the obj-ect of my invention to provide improvements in such chucks, and means by which the drill can be more securely locked in place, and easily removed from the chuck when required.

A is the chuck having a bore made into one end to receive the dr-ill shank 2.

3 is a bushing such as is commonly used in rock drills. Opposed to this bushing is the key 4 which lits into a chamber upon the opposite side ot the chuck 'from the bushing 3, and the key has a segmental channel on its inner'face corresponding with and opposed to the bushing so that when the drill shank has been'inserted between the two, the key may be drawn firmly against the shank by bolts, thus clamping the drill shank lirmly in place. rl`his key is preferably made oval in transverse section, as shown in Fig. l, but it might be made round or of other forms.

The segmental channel which lits the drill shank is made a little larger or slack at the ends as indicated at 4 Fig. 3 so that it acts as an equalizer, making the strain always the same on both bolt-holes, and holding the drill very securely, while at the same time saving the holes.

Holes are bored through the key and the chuck to receive the holding bolts 5, and by means of nuts 6 screwed upon the ends of the bolts, the parts are clamped together to bind upon thel drill. Y

ln my 'invention l countersink one hole in the key which receives the bolt-head, and the hole upon the opposite side oi" the chuck which receives the other bolt-head, so that these bolt-heads lie substantially ilush upon opposite sides and the nuts (i correspondingly projeot upon the opposite ends ot the bolts which extend through the chuck and the key.

By this construction it is possible to apply a wrench and remove the nuts without interlering with the head et the other bolts, and it also makes it easy to get at both ends without turning the chucks which it is necessary to do with the ordinary construction ol'v chucks and which is dillicult il" the drill sticks in the hole.

l lith this chuck the miner can get at both nuts without turning the chuck since they are on opposite sides.

In order to prevent the bolts `from turning' when setting up the nuts, the bolt-heads 7 are made eccentric to the shank of the bolt, and the key et and chuck A are bored to receive these eccentric heads as shown, so that when they are in place, the nuts can easily be turned on or oil' without any danger ol turning the bolts.

lt will be understood that the heads might be made polygonal and the correspondingly shaped socket made to receive them, but the lorm here shown enables the sockets to be bored out, and ol inexpensive construction.

llaving thus described my invention, what I claim and desire to secure by Letters Patent is l. A drill chuck having a socket to receive the drill shank, a key fitting a chamber upon one side ot the shank, and adapted to be compressed upon the drill shank, bolts extending through the key and the chuck upon opposite sidesy ol the drill shank, said bolts having cylindrical heads eccentric to the body portion, correspondingly shaped sunken chambers inthe key and the chuck upon opposite sides adapted to receive the heads ol2 the bolts and nuts turnable upon the opposite ends ot the bolts to lock the drill shank in the chuck, said chambers and bolt holes not 'intersecting the segmental drill-holding channels.

lOO

2. A drill chuck having a socket and a In testimony whereof I have hereunto set drlll shank httlng therem, a key ttlng a j my hand in presence of two subserlbngwit- 1o Countersunk chamber upon one side of the nesses.

Chuck, and bolts by Whoh said key is Caused I f v to Clamp the drill shank Within the Chuck, CHARLES A' HLLTQUIST said key having the ends Constructed to l/Vtnesses:

make a slack ft whereby the key aets as an JAS. BERGMAN,

equalizer for the strain upon the bolts. F. J. HOGAN. 

